Drum



March 16, 1937. c. H. STRUPE DRUM 4 SheetsSheet 2 Filed June 14, 1934 ||||I Hlllll lllllll 2 mm 5 m.

ATTORN E 3'5 March 16, 1937. c STRUPE 2,074,193

DRUM

Filed June 14, 1934 4 Sheets-Sheet 3 INVENTOR.

0601711. Suva 0e, BY

ATTORNEYS March 16, 1937, c. H. STRUPE DRUM 4 Sheets-Sheet 4 Filed June' 14, 1934 Patented Mar. 16, 1937 UNITED STATES atr a FFIQE 4 Claims.

The object of my invention is to produce a drum having improved means by which the heads may be individually tensioned and, in the case of snare drums, by which the snares may be individually tensioned and unitarily moved to and from effective position.

The accompanying drawings illustrate my invention.

Fig. 1 is a diametrical fragmentary section of a snare drum embodying my invention, the

snares being omitted;

Fig. 2 is a plan with the upper head removed;

Fig. 3 is a fragmentary section, on a larger scale, of the snare mechanism;

Fig. 4 is a section, on the scale of Fig. 3, on line 4-4 of Fig. 2;

Fig. 5 is an elevation of one end of the snare mechanism;

Fig. 6 is a fragmentary inside elevation showing the inner ends of levers 2|;

Fig. '7 is a fragmentary side elevation partly in section showing a modified form of the snare mechanism;

Fig. 8 is an end view of one of the snare holders;

Fig. 9 is an end view of the opposite snare holder;

Fig. 10 is a sectional View on the line ID, H] of Fig. 8, and

Fig. 11 is a sectional view on the line H, H of Fig. 9.

In the drawings Ill indicates the open-ended cylindrical shell of the drum, l I, H the head rings, l2, l2 the associated heads, and i3, i3 7 the associated straining rings each having radially projecting perforated ears Id through each of which is projected an adjusting screw l5.

Secured to the exterior of shell I!) are circumferentially spaced housings !6 corresponding in number and spacings with the ears l4 and mounted in each housing are two oppositely projected tubes i1 each internally threaded at its outer end to receive a screw 15. Each tube H at its inner end is slotted at l8 and opposite the slot, is provided with a cross-pin l9. Pivoted at 20, 20 in each housing adjacent the inner end of each tube I1 is a lever 2| the outer end of which is projected through a slot l8 and overlies a cross-pin l9 and the inner end of which is projected, through slot 22, into the interior of shell ID.

The inner end of each lever 2| is formed into a hook 23 which enters the eye 24 formed in the outer end of a link 25. The levers ZI- and links 55 25 are arranged in upper and lower series. The

inner ends of the two series of links 25 are respectively converged tangentially toward and pivotally connected to actuating rings 26, 26 each of which is provided with an arm 27.

The two actuating rings 26, 26 are centrally journalled on the upper and lower faces of an anchor plate 30 at the opposite ends of which are journalled two adjusting screws 3!, 3| which are projected through shell iii and provided with thumb heads 3| by which they may be readily turned from the exterior of the shell. Mounted on each screw 3! is a nut 32 which is journalled upon one end of a link 33 the opposite end of which is pivotally connected at 34 with an arm 2?, the arrangement being such that turning of screw 3! correspondingly turns the connected ring 26 to pull or relieve the connected series of links 25.

Even tensioning of each drum head 52 is obtained by individual adjustment of the screws 55 cooperating with the straining ring i3 for that head, whereupon desired increase or decrease of tension in a head l2, without substantially affecting the opposite head I 2, may be obtained by turning the appropriate screw 3!. Turning of one of the actuating rings 2% uniformly affects the links 25 attached thereto and these links uniformly affect their levers 2! which, in turn uniformly affect the tubes I! and screws IE to which they are connected so that the associated straining ring is uniformly affected and consequently the associated head ring and head may be quickly tightened or loosened uniformly.

As shown in Fig. 6 the slots 22 are medially widened to facilitate the inward projection of levers 2| whose inner ends are relatively laterally displaced to facilitate assembly of links 25 therewith.

Secured to the outside of shell H3, at diametrically opposite points are two posts M3 to each of which is pivoted a U-shaped link to which is pivoted the bifurcated upper end of a depending arm 42 provided with a downwardly-presented heel 43 and a cross bar 44 laterally spaced from the heel. Detachably secured to heel 43 of one of the arms is a perforated plate 45 through which the snares 46 are strung and both ends of these snares are carried over the adjacent cross bar 44 and projected through the adjacent straining ring and across the drum head again through the straining ring and over the cross bar 44 of the other arm 32 to the adjacent heel 43 upon which the ends of the snares are clamped by the bar 47 through which the clamping screws 48 are projected into said heel.

In this arm 42, above its heel 83, there are pivoted a number of triangular levers 59 corresponding in number and registering with the several snares, one arm of each lever being engageable with a snare. The other arms of said levers are engaged respectively by temper screws 53 which are threaded through this arm 42 above the heel so that the snares may be individually strained by proper adjustment of the levers 5t.

Secured to the inside of shell til in radial alignment with the arms 12 are brackets 66 in each of which is pivoted a bell crank lever 6! provided at the ends of its two arms with trunnioned nuts 62 and 63. Each nut 62 receives the threaded portion of a screw G l which is pro jected through the adjacent arm %2 and through the shell It and provided at its outer end with a knurled nut, by means of which it may be readily manipulated. The two nuts 63 are connected together by a stretcher rod 65 and the two bell crank levers are reversely set in their respective brackets, with their arms which carry the nuts 62 approximately parallel with the adjacent drum head when said levers are in their medial positions.

Attached to one of the links ll, so as to form an operating arm therefor, is a finger 6'! which is projected upwardly to a point somewhat above the plane of the upper drum. head.

By swinging the upper end of finger 6'! outwardly, the link 4! to which it is attached is swung downwardly thereby lowering the arm 42 which depends therefrom and the movement of this arm, through the medium of its screw 64,

H swings the adjacent bell crank lever which,

through the medium of the stretcher rod swings the other bell crank lever which, through the medium of its nut 62 and associated screw 56 causes the other depending arm 42 to move downwardly so that the snares are moved away from the adjacent drum head in substantial parallelism therewith. Movement of the finger 67 back to the position shown in the drawings brings the snares in parallelism up against the adjacent drum head.

As shown in Fig. 3, the nuts 63 pass across the dead centers of the bell crank levers as arms 52 pass from upper to lower position or vice versa, so that the tension in the snares acts to hold the parts in either extreme.

It will be noticed that one arm of each bellcrank-lever 6! projects from the pivotal anchorage of the lever toward the adjacent snare-carrying arm 42 and this arm or lever 6| is so arranged that its outer end crosses a plane through the lever axis and parallel with the drum head so that each of said bell-crank arms, in conjunction with the strut screw E l, forms a sort of toggle the knuckle of which is carried over an intermediate dead center as the snares are shifted to or away from the drum head. As a result of this arrangement the tension in the snares acts to yieldingly hold the snares in either extreme of lateral adjustment.

It will, of course, be apparent that, if desired, lateral snare movement need only be provided at one end, in which case the range of movement should be somewhat greater.

I have illustrated a modified form of snare mechanism in Figs. 7 to 11 inclusive. In this structure a U-shaped member is secured to the side of the drum near the bottom, the two arms 68 of which extend substantially at right angles to the shell. A snare clamp 59 is pivotally connected to these arms through the instrumentality of links 10 pivoted to the sides of the clamp and to the ends of the arm. This clamp is somewhat V-shaped with the base of the V extending towards the bottom of the drum and provided with a pair of downwardly extending arms H between which is swivelly mounted one snare clamping member E2. The other snare clamping member 13 is adapted to be connected to the first-mentioned member by means of tightening screws 14 and between these members is inserted a soft metal bearing member Hi. Also mounted on the shell is a post 75 on which is swingably or pivotally mounted a bell crank lever the longer arm 16 of which provides a finger mechanism for tightening or releasing the snares by vertically moving the snare clamp 69. The shorter arm T! of this lever is connected to a vertically movable arm l'B by means of a pivoted link 79 and this vertically movable arm has the clamp 69 pivoted thereto by the same pivot pins 38 as connect the links m to the snare clamp. By this arrangement the snare clamp may be vertically moved and at the same time the clamp is rockably mounted relatively to the shell. For adjust ing this rocking movement I provide a set screw 8! threaded into the arm 78 and having a head 82 bearing on the upper end of the snare clamp. In order to guide the vertically movable member 18 this member is slotted as at 83 to take the pivot pin of the lever 76.

Mounted on the shell diametrically opposite the snare clamp 69 is provided another snare clamp comprising a pair of arms 84 connected together by an integral cross bar 85, .which are pivoted as at B6 to the T head 81 of a supporting post 88 mounted on the drum shell. These arms 84 have secured between them at their lower ends a clamp similar to the clamp comprising the members i2 and 13 for gripping the snares. This snare clamp extends at an angle outwardly and inwardly towards the shell and is biased to swing towards the vertical position by a coiled spring 89 fitting in a recess in the post 88 and having one end bearing upon the upper side of the cross bar 85. It is therefore apparent that, due to the angular disposition of this clamping member, when the snare clamp 69 is lowered the tension on the snares will be somewhat relieved and under the influence of the spring 85, the snares at their opposite ends will also be lowered. Furthermore, it is to be noted that by the swinging of the snare clamp on its pivot 88 to move the lower end of the snare clamp in or out, a corresponding movement will taken place with the opposite snare clamp.

In Figs. 7 and 8 I have also illustrated a modified form of tension ring. It will be noted that in the structures illustrated in Figs. 1 to 6, inclusive, especially as shown in Fig. 5, a casting is provided at the point where the tension ring is slotted to accommodate the snares. In place of this casting I have illustrated in Figs. 7, 8 and 9 a modification. In this structure the tension ring !3, instead of being slotted is pierced by an opening 99 and the metal at the bottom edge of the ring is then drawn down to form an integral bridge 9|. By this means sufiicient clearance is provided for the lowering of the snares without their coming in contact with the tension ring and, at the same time, the tension ring is given sufiicient rigidity to prevent give at any point.

I claim as my invention:

1. In a drum, the combination with the main shell, a head, a head ring, and a straining ring, of a plurality of circumferentially spaced levers pivotally mounted on the shell, a corresponding circumferentially spaced series of variable length connectors between and connected to said levers and strained ring, a corresponding series of inwardly converging links connected with said levers, operating means accessible from the exterior of the drum and operatively connected to said links for simultaneously imparting to the converging ends of said links a rotary movement to simultaneously shift said levers.

2. In a drum, the combination with the main shell, a head, a head ring, and a straining ring, of a plurality of circumferentially spaced levers pivotally mounted on the shell, a corresponding circumferentially spaced series of variable length connectors between and connected to said levers and straining ring, an actuator ring corresponding series of inwardly converging links connected with said levers and with said actuator ring, an anchor plate mounted within the shell, a threaded rod journalled on said anchor plate and projected through the drum shell and accessible from the exterior thereof, a nut on said rod, said actuator ring being journalled on the anchor plate, and a link connecting said nut and said actuator ring.

3. In a drum, in combination a main shell, a plurality of circumferentially spaced housings secured to the exterior thereof, two series of levers, one lever of each series being pivoted in each of said housings, each of said levers having one arm projectable through the drum shell, a

pair of straining rings mounted on the drum shell at opposite ends thereof, two oppositely extending variable length connectors extending respectively between and connected to said levers and straining rings, and two independently manipulable operating elements, each accessible from theexterior of the drum, and each connected to the levers of one of said series for independently manipulating said two series of levers.

4. In a drum, in combination a main shell, a plurality of circumferentially spaced housings secured to the exterior thereof, a pair of levers pivoted in each of said housings, each of said levers having one arm projectable through the drum shell, a pair of straining rings mounted on the drum shell at opposite ends thereof, two oppositely extending variable length connectors extending respectively between and connected to said levers and straining rings, an anchor plate mounted within the main shell, two threaded rods journalled on said anchor plate with their outer ends projected through the main shell and manipulable from the exterior thereof, two actuator rings independently journalled on said anchor plate, two series of links respectively connecting each actuator ring with a circumferential series of levers, and independent connections between each threaded rod and one actuator ring.

CECIL H. S'IRUPE. 

